The fate of oral uptake and injected ammonia as the stable isotope 15NH4Cl on nitrogen metabolism in the American cockroach, Periplaneta americana L

The American cockroach has been described as externally ammonotelic but internally uricotelic.  This insect contains two microbial populations either residing in their hindgut or contained in fat body mycetocytes.  It appears that both of these microbial populations play a significant role in cockroach nitrogen metabolism, linked to relationships of ammonia metabolism between these three organismic units.  This study reports on an assessment of nitrogen metabolism in these insects maintained on various nitrogen diets with or without antibiotics when provided with dietary or injected with¹⁵N enriched NH₄Cl.